System and method of encoding units of data including entity/relationship data, function calls, and file data using a common data format (CDF) according to formal CDF grammar rules

ABSTRACT

Method and means are described for encoding and decoding stored units of data representing entity/relationship (E/R) data, function calls, and file data by including a prefix with each unit of data which includes a length code, an action code, and a unit identifier code. The data units with prefixes are organized into a data stream by using rules described in a formal grammar. The data stream will typically be transmitted to another program inside the computer or to another computer--host or PWS. When received the data stream is parsed back into data units by reversing the encoding process. After the data units are recovered the appropriate action is taken to process the units. E/R data is entered into or updated in a repository, function calls are passed on to an E/R repository function or other program along with the specified parameters for execution, and file data is stored in standard files. Generated output is captured, encoded into a data stream and transmitted back to requesting PWS which then parses the data stream to recover the output data.

This application is a divisional application of Ser. No. 07/796,117, filed Nov. 20, 1991, now U.S. Pat. No. 5,355,493.

FIELD OF THE INVENTION

The present invention relates to systems and methods for encoding, decoding, moving and manipulating computerized data and more particularly data relating to entities and relationships.

BACKGROUND OF THE INVENTION

As used in the field of this invention, entities and relationships are special forms of data that are intended to represent information that is useful in the process of designing and writing computer programs. When this information is stored in a retrievable manner it can be used to aid in the development of computer programs. There are various commercial software systems available which are specially designed to manipulate entity/relationship (E/R) data. One of these systems is IBM's Repository Manager (RM). RM is a predominantly host computer based program. Users of RM may enter their data manually using dialog panels or custom programs may be developed to create, update and retrieve the data. RM provides a set of callable functions which can be accessed by other programs. New RM functions can be created by users as well. These callable functions typically require one or more parameters to perform correctly. It is standard practice in the industry for users to have a personal computer or programmable workstation (PWS) which is used to interface with host computer based programs. When the PWS is sharing the workload with the host, the system is said to be "cooperative". Many kinds of data, not only E/R data, are stored in files. These files may be located on either the host or the PWS.

There is a need for efficient ways to encode E/R data, function calls, and file data in a format which can be transmitted between a PWS and another computer.

Packaging data in a data format of self-describing units is known in the art. The use of grammars as a way of precisely defining syntax is also well known. An efficient comprehensive grammar for self-describing data stream of E/R related data which meets the described need is not found in the prior art.

SUMMARY OF THE INVENTION

The invention provides method and means for encoding and decoding stored units of data representing entity/relationship data, function calls, and file data by including a prefix with each unit of data which includes a length code, an action code, and a unit identifier code. The data units with prefixes are built into a data stream by using rules described in a formal grammar. The data stream can be stored in temporary or permanent storage in the computer. It may be transmitted to another program on the same computer or to another computer--host or PWS. When received the data stream is parsed back into data units by reversing the encoding process. After the data units are recovered the appropriate action may be taken to process the units. E/R data may be entered into or updated in a repository, function calls may be passed on to the appropriate functions along with the specified parameters for execution, and file data may be stored. Generated output data is captured, encoded and returned to the requesting system as a data stream which must be parsed.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the block structure of a PWS and host using the invention.

FIG. 2 shows the overview of the steps involved in executing a function call using the invention.

FIG. 3 shows an overview of the build process of the invention.

FIG. 4 shows a representation of a Template Tree Instance used as an example.

DETAILED DESCRIPTION OF THE INVENTION

The invention is embodied in a larger system which will be called the Entity/Relationship Data Movement and Manipulation tool (EDMM) which is designed for use with IBM's Repository Manager/MVS. The invention is, however, independent of the particular host tool used as the repository for the E/R data. EDMM has five components. The first four components described are run-time facilities; the fifth, PF, is used during development. Each of these components is described in detail in later sections. They are:

1. Common Data Format (CDF): EDMM's common data interchange format, which is a means of consistently representing E/R, file record data and function call information within a data stream.

2. Builder: The function that creates a CDF data stream from E/R, file record and function call data.

3. Parser: The function that interprets and decodes information in a CDF data stream.

4. Communication Facility (CF): The function which provides data transfer and remote function routing between work station and host platforms.

5. Productivity Facility (PF): The facility for creating Repository Manager data handling functions based on the work station tool's view of the E/R data.

The overall structure of a host connected PWS system using the invention is shown in FIG. 1. The invention can be used in any system requiring transmission or storage of E/R related data. Thus, a PWS to PWS or host to host connection will work, as will any combination of networked computers. The operation of the system is controlled by a user supplied Application Program 26 which supplies the data and commands for the components of EDMM. The components of the invention are an EDMM Builder, Parser, and Communication Facility. The PWS Builder 11 is required to encode the raw units of data into a formatted data stream. The PWS Parser 15 decodes a formatted data stream. The PWS Communication Facility (CF) 13 provides the high level interface to a standard computer-to-computer communication means 17. Host Builder 12, Host Parser 16, and Host Communication Function 14 provide similar function on the host side, but the internals may be different because the host computer may have an instruction set or operating system that is different than that of the PWS. The Host Communication Function also includes a Router 22, which provides means to detect the presence of and appropriately route the E/R data, function calls, and file data in the data stream. The Function means 20 may be a part of EDMM, may be supplied as a part of a system such as the Repository Manager and/or may include functions supplied by the operating system. E/R data from the PWS is routed to Load means 19. The Unload means 21 is used to retrieve E/R data from the repository and return it to the PWS. The E/R data is stored in the repository means 18 such as is provided through IBM's Repository Manager/MVS. File data is stored in whatever standard way is provided by the operating system such as an MVS partitioned data set (PDS) 23. The Load, Unload, and other Functions may generate output which is captured and routed back to the PWS through the link.

A CDF data stream consists of units of binary and character data. Each unit contains a self-describing prefix area followed by a variable-length data area that might contain other nested units. The prefix area contains a 4-byte length field, a 1-byte action field, and a 1-byte unit identifier field. The data area may or may not contain data depending upon the type of unit being described.

The CDF data stream is supported by two functions, the Parser and the Builder, which exist on both the work station and the host. These functions provide users with an external view of a CDF data stream by dealing with the complexities of the CDF as well as ensuring the syntactical correctness of the data stream. Any function that deals with a CDF data stream must go through the Builder and Parser. The purpose of the Builder is to build a CDF data stream one unit at a time. The purpose of the Parser function is to retrieve data one unit at a time from a CDF data stream. It allows the user to interpret data in the CDF.

The Communication Facility is the component of the EDMM Tool that allows the communication of remote function calls and other information between work station tools and host-based Repository Manager functions. This component relies on RM/PWS, which is supplied with the Repository Manager, to communicate between the host and the work station. A tool on the work station invokes the CF function on the work station, passing it a CDF data stream containing function call information and any other data necessary to invoke that function. The Host CF interprets the CDF data stream and routes the function calls to the appropriate host Repository Manager function. After the Repository Manager function(s) have executed, the output parameters and processing results are returned to the work station tool in another CDF data stream.

The Productivity Facility(PF) is the component that enables the rapid creation of data manipulation functions based on a variety of views of E/R data in the repository. The PF creates Repository Manager data handling C-Language functions, as described below, for any configuration of entities and relationships defined by the user.

Unload

A function that retrieves a group of connected entities and relationships from the repository and translates the entity, attribute, and relationship information via the Builder function into a CDF data stream.

Load

A function that interprets a CDF data stream containing entity, attribute, and relationship information, updating the repository as specified by the action field of each CDF unit.

Delete

A function that deletes a group of connected entity and relationship instances from the repository.

Copy

A function that copies a group of connected entity and relationship instances in the repository.

To create an Repository Manager function using PF, the tool builder must first fully define the function to Repository Manager, and generate the Repository Manager function report. The generated Repository Manager report is input to the Productivity Facility, which produces the desired Repository Manager C-Language function based on the tool builder's view of the E/R data. A fully defined Repository Manager function includes the definition of templates and connections.

EDMM Run-time Scenario

FIG. 2 will be used to illustrate the overall process of how a work station application and the host interact when the arbitrary function, which will be called FUNCTION₋₋ X, on the host is called from the work station. This scenario can easily be generalized for any activity requested by the application on the work station.

The scenario is as follows:

1. The application on the work station uses the Builder function to build a CDF data stream, specifying the FUNCTION₋₋ X function to be invoked on the host along with FUNCTION₋₋ X's input parameter values 31. The data stream may be stored temporarily (in RAM) or more permanently on disk or tape.

2. The application on the work station transmits the data stream to the host by invoking CF on the work station using a regular C function call, passing a pointer to the CDF data stream as input 32. If the host uses a character set which is different from the PWS, then a character set translation is performed by the PWS CF before the data is transmitted.

3. The CF function on the work station transfers the CDF data to the CE counterpart on the host.

4. After parsing the data stream 33, the routing is performed 34 based on the FUNCTION₋₋ X function call information in the CDF data stream, the CF router function on the host sets up the appropriate FUNCTION₋₋ X parameter template with input parameter values from the data stream and invokes the FUNCTION₋₋ X host Repository Manager function.

5. The FUNCTION₋₋ X function processes.

6. Upon completion, the FUNCTION₋₋ X function sets the output parameter values and returns to the host CF function with its output parameters in the FUNCTION₋₋ X Repository Manager parameter template 35. Some functions might only generate a return code, but the return code will be processed through the builder the same as other types of data.

7. The CF function on the host takes output parameters from FUNCTION₋₋ X's parameter template and, using the Builder function 36, places them back into the CDF data stream to be returned to the CF function on the work station.

8. The CF function on the host returns the CDF data stream to its counterpart CF function on the work station. If character set translation is required, it is performed by the CF after the data is transmitted back to the PWS. The CF function on the work station returns the CDF data to the application 37.

9. The application uses the Parser function 38 to obtain results of the host function call from the CDF data stream, displaying the results to the user where necessary via dialogs, pop-up windows, etc.

Function calls can include E/R data or file data as input or out parameters. The process of handling E/R data coming from the PWS is also similar, but in this case the routing will invoke the Load means which places the E/R data into the repository. Requesting the Unload function results in outputting E/R data that is encoded and sent back to the PWS.

In FIG. 3 an overview of the build process is shown. When the first unit is processed 41 the initialization of memory, etc. is performed 42. If the last unit has been processed 43, then the data stream is constructed from the unit data which has been previously stored in tree form in memory 44. Since the requests from the application program must be a correct sequence, the sequence must be validated 45. The builder and parser are both driven using finite state automata techniques. The state table will be described in detail in Table 1 later. Since only certain state transitions are valid, these are also checked 46. The data for the unit is then stored in a tree in memory for later use in building the final data stream 47.

The parsing process is the reverse of the build process. The application program passes the parser a pointer to a data stream in memory or gives a file name which contains the data stream. The parser returns one unit at a time back to the application program. The parser keeps its own internal pointer into the data stream. The state table of Table 1 describes the details of the state transitions.

FIG. 4 shows a representation of a Template Tree Instance which will be used as an example. The data stream built from this Instance is 222 bytes long. The hexadecimal representation of this data stream is as follows:

    __________________________________________________________________________     000000DE                                                                             00020000                                                                             002F0403                                                                             D7C5D9E2                                                                             D6D54040                                                                              0000000C                                                                             0005F1F2                                                                             F4F4F5F6                            00000015                                                                             0406D5C1                                                                             D4C54040                                                                             4040D4C9                                                                             C3C8C1C5                                                                              D3000000                                                                             150403D4                                                                             D6C4E4D3                            C5404000                                                                             00000700                                                                             05C10000                                                                             003F0407                                                                             F0F0F0F0                                                                              F0F0F0F0                                                                             F0F10000                                                                             001A0009                            D7C5D9E2                                                                             D6D54040                                                                             0000000C                                                                             0005F1F2                                                                             F4F4F5F6                                                                              00000015                                                                             0009D4D6                                                                             C4E4D3C5                            40400000                                                                             00070005                                                                             C1000000                                                                             180403C9                                                                             D5E36DD7                                                                              D9D6C300                                                                             00000A00                                                                             05D7E4E2                            C8000000                                                                             3D0407F0                                                                             F0F0F0F0                                                                             F0F0F0F0                                                                             F2000000                                                                              150009D4                                                                             D6C4E4D3                                                                             C5404000                            00000700                                                                             05C10000                                                                             00180009                                                                             C9D5E36D                                                                             D7D9D6C3                                                                              0000000A                                                                             0005D7E4                                                                             E2C80000                            00000000                                                                             00000000                                                                             00000000                                                                             00000000                                                                             00000000                                                                              00000000                                        __________________________________________________________________________

In the following the hexadecimal/character representation of a CDF Data Stream is broken down unit. The prefix is the first 6 bytes. The length is the first 4 bytes of the prefix, the action is the next byte of the prefix, and the id is the last byte of the prefix. The rest of the line is the data (this is of varying length).

    __________________________________________________________________________     000000DE 0002                                                                  Length=222, action=0 (NONE), id=2 (E/R.sub.-- DATA.sub.-- GROUP.sub.--         ID), data=none.                                                                0000002F 0403D7C5D9E2 D6D54040                                                 Length=47, action=4 (READ), id=zz (TMPL.sub.-- ID), data= PERSON               0000000C 0005F1F2 F4F4F5F6                                                     Length=12 , action=0 (NONE), id=5 (TMPL.sub.-- KEY.sub.-- ID), data=           124456                                                                         00000015 0406D5C1 D4C54040 4040D4C9 C3C8C1C5 D3                                Length=21 , action=4 (READ), id=6 (FIELD.sub.-- ID), data= NAME MICHAEL        00000015 0403D4D6 C4E4D3C5 4040                                                Length=21 , action=4 (READ), id=3 (TMPL.sub.-- ID), data= MODULE               00000007 0005C1                                                                Length=7 , action=0 (NONE), id=5 (TMPL.sub.-- KEY.sub.-- ID), data= A          0000003F 0407F0F0 F0F0F0F0 F0F0F0F1                                            Length=63 , action=4 (READ), id=7 (REL.sub.-- ID), data= 0000000001            0000001A 0009D7C5 D9E2D6D5 4040                                                Length=26 , action=0 (NONE), id=9 (RELENT.sub.-- KEY.sub.-- ID), data=         PERSON                                                                         0000000C 0005F1F2 F4F4F5F6                                                     Length=12 , action=0 (NONE), id=5 (TMPL.sub.-- KEY.sub.-- ID), data=           124456                                                                         00000015 0009D4D6 C4E4D3C5 4040                                                Length=21 , action=0 (NONE), id=9 (RELENT.sub.-- KEY.sub.-- ID), data=         MODULE                                                                         00000007 0005C1                                                                Length=7 , action=0 (NONE), id=5 (TMPL.sub.-- KEY.sub.-- ID), data= A          00000018 0403C9D5 E36DD7D9 D6C3                                                Length=24 , action=4 (READ), id=3 (TMPL.sub.-- ID), data= INT.sub.--           PROC                                                                           0000000A 0005D7E4 E2C8                                                         Length=10 , action=0 (NONE), id=5 (TMPL.sub.-- KEY.sub.-- ID), data=           PUSH                                                                           0000003D 0407F0F0 F0F0F0F0 F0F0F0F2                                            Length=61 , action=4 (READ), id=7 (REL.sub.-- ID), data= 0000000002            00000015 0009D4D6 C4E4D3C5 4040                                                Length=21 , action=0 (NONE), id=9 (RELENT.sub.-- KEY.sub.-- ID), data=         MODULE                                                                         00000007 0005C1                                                                Length=7 , action=0 (NONE), id=5 (TMPL.sub.-- KEY.sub.-- ID), data= A          00000018 0009C9D5 E36DD7D9 D6C3                                                Length=24 , action=0 (NONE), id=9 (RELENT.sub.-- KEY.sub.-- ID), data=         INT.sub.-- PROC                                                                0000000A 0005D7E4 E2C8                                                         Length=10 , action=0 (NONE), id=5 (TMPL.sub.-- KEY.sub.-- ID), data=           __________________________________________________________________________     PUSH                                                                      

The printable Parser output for this data stream is:

    ______________________________________                                         E/R.sub.-- DATA.sub.-- GROUP.sub.-- ID                                                          NONE                                                          TMPL.sub.-- ID   READ     PERSON                                               TMPL.sub.-- KEY.sub.-- ID                                                                       NONE     124456                                               FIELD.sub.-- ID  READ     NAME MICHAEL                                         TMPL.sub.-- ID   READ     MODULE                                               TMPL.sub.-- KEY.sub.-- ID                                                                       NONE     A                                                    REL.sub.-- ID    READ     0000000001                                           RELENT.sub.-- KEY.sub.-- ID                                                                     NONE     PERSON                                               TMPL.sub.-- KEY.sub.-- ID                                                                       NONE     124456                                               RELENT.sub.-- KEY.sub.-- ID                                                                     NONE     MODULE                                               TMPL.sub.-- KEY.sub.-- ID                                                                       NONE     A                                                    TMPL.sub.-- ID   READ     INT.sub.-- PROC                                      TMPL.sub.-- KEY.sub.-- ID                                                                       NONE     PUSH                                                 REL.sub.-- ID    READ     0000000002                                           RELENT.sub.-- KEY.sub.-- ID                                                                     NONE     MODULE                                               TMPL.sub.-- KEY.sub.-- ID                                                                       NONE     A                                                    RELENT.sub.-- KEY.sub.-- ID                                                                     NONE     INT.sub.-- PROC                                      TMPL.sub.-- KEY.sub.-- ID                                                                       NONE     PUSH                                                 ______________________________________                                    

Common Data Format

The Common Data Format (CDF) provides a consistent means of communicating data among host and work station functions. It supports communication of E/R instance data and file data. In addition, it allows work station users to indirectly invoke host functions and receive results of host function processing. The CDF will be formally described.

CDF Basic Format

The CDF consists of units of data used to represent entity, attribute, and relationship instance data, function call information including parameters, and file data. Each CDF unit has a self-describing prefix area followed by a variable-length data area. The prefix area contains a 4-byte length field, a 1-byte action field, and a 1-byte unit identifier field. The data area may or may not contain data depending upon the type of unit being described.

The CDF data stream grammar is described below. Functions that deal with data in the CDF should not maintain or otherwise handle the CDF data stream directly; this information is maintained by the Builder and Parser functions. Note also that CDF data streams consist of binary and character data. The prefix area is represented in binary and the data area in character.

CDF Formal Grammar

This section contains a formal description of the CDF grammar. It shows the units that can make up a CDF data stream as well as the semantics that go along with those units. All CDF data streams must conform to this formal grammar in order to be processed by the Builder and Parser functions.

Standard Backus Naur Form (BNF) notation is used to document this description.

    __________________________________________________________________________     Non-terminals                                                                  <cdf.sub.-- data.sub.-- stream>                                                            ::= <edmm.sub.-- data.sub.-- stream> | <er.sub.--                     data.sub.-- group> | <file.sub.-- data.sub.--                         group>                                                             <edmm.sub.-- data.sub.-- stream>                                                           ::= length <no.sub.-- action> edmm.sub.-- data.sub.--                          stream.sub.-- id <edmm.sub.-- data.sub.-- list>                    <edmm.sub.-- data.sub.-- list>                                                             ::= <edmm.sub.-- data> <edmm.sub.-- data.sub.-- list>                          | <edmm.sub.-- data>                                      <edmm.sub.-- data>                                                                         ::= <function.sub.-- call> | <function.sub.-- call>                   <er.sub.-- data.sub.-- group> |                                        <function.sub.-- call> <file.sub.-- data.sub.-- group>            <function.sub.-- call>                                                                     ::= length <no.sub.-- action> fun.sub.-- call.sub.-- id                        fun.sub. -- name <fun.sub.-- parm.sub.-- list>                     <fun.sub.-- parm.sub.-- list>                                                              ::= <fun.sub.-- parm> <fun.sub.-- parm.sub.-- list> |                  <NULL>                                                            <fun.sub.-- parm>                                                                          ::= length <no.sub.-- action> fun.sub.-- parm.sub.-- id                        fun.sub.-- parm.sub.-- name                                                     fun.sub.-- parm.sub.-- value                                      <er.sub.-- data.sub.-- group>                                                              ::= length <no.sub.-- action> er.sub.-- data.sub.-- group.sub.                 -- id <er.sub.-- data.sub.-- list>                                 <er.sub.-- data.sub.-- list>                                                               ::= <er.sub.-- data> <er.sub.-- data.sub.-- list> |                   <er.sub.-- data>                                                   <er.sub.-- data>                                                                           ::= <template> | <rel>                                    <template>  ::= length <crud.sub.-- action> tmpl.sub.-- id                                 template.sub.-- name                                                            <tmpl.sub. -- key.sub.-- list> <field.sub.-- list>                <tmpl.sub.-- key.sub.-- list>                                                              ::= <tmpl.sub.-- key> <tmpl.sub.-- key.sub.-- list> |                  <tmpl.sub.-- key>                                                 <tmpl.sub.-- key>                                                                          ::= length <no.sub.-- action> temp.sub.-- tmpl.sub.--                          key.sub.-- id <temp.sub.-- key> |                                      length <no.sub.-- action> tmpl.sub.-- key.sub.-- id                           key.sub.-- value                                                   <field.sub.-- list>                                                                        ::= <field> <field.sub.-- list> | <NULL>                  <field>     ::= length <crud.sub.-- action> field.sub.-- id field.sub.--                   name field.sub.-- value                                            <rel>       ::= length <crd.sub.-- action> rel.sub.-- id <rel.sub.-- key>                  <source.sub.-- key>                                                             <target.sub.-- key> |                                                 length <cu.sub.-- action>  orel.sub.-- id <rel.sub.-- key>                    <rel.sub.-- posn>                                                               <source.sub.-- key> <target.sub.-- key>                           <source.sub.-- key>                                                                        ::= <relent.sub.-- key> | <relrel.sub.-- key>             <target.sub.-- key>                                                                        ::= <relent.sub.-- key> | <relrel.sub.-- key>             <relent.sub.-- key>                                                                        ::= length <no.sub.-- action> relent.sub.-- key.sub.-- id                      template.sub.-- name                                                            <tmpl.sub.-- key.sub.-- list>                                     <relrel.sub.-- key>                                                                        ::= length <no.sub.-- action> relrel.sub.-- key.sub.-- id                      rel.sub.-- key                                                     <file.sub.-- data.sub.-- group>                                                            ::= length <no.sub.-- action> file.sub.-- data.sub.--                          group.sub.-- id <file.sub.-- data.sub.-- list>                     <file.sub.-- data.sub.-- list>                                                             ::= <line> <file.sub.-- data.sub.-- list> | <line>        <line>      ::= length <no.sub.-- action> line.sub.-- id line.sub.--                       value                                                              <crud.sub.-- action>                                                                       ::= create | read | update |                        delete                                                             <cu.sub.-- action>                                                                         ::= create | update                                       <crd.sub.-- action>                                                                        ::= create | read | delete                       <c.sub.-- action>                                                                          ::= create                                                         <no.sub.-- action>                                                                         ::= none                                                           <temp.sub.-- key>                                                                          ::= unique.sub.-- key                                              <rel.sub.-- key>                                                                           ::= unique.sub.-- key                                              <rel.sub.-- posn>                                                                          ::= unique.sub.-- key | 0                                 <NULL>      ::=                                                                Terminals                                                                      length      ::= Binary(4) - Length of unit (including the prefix                            (length(4), action(1), and unit id(1)) plus data)                 none        ::= Binary(1) 00                                                   create      ::= Binary(1) 01                                                   delete      ::= Binary(1) 02                                                   update      ::= Binary(1) 03                                                   read        ::= Binary(1) 04                                                   edmm.sub.-- data.sub.-- stream.sub.-- id                                                   ::= Binary(1) 00                                                   fun.sub.-- call.sub.-- id                                                                  ::= Binary(1) 01                                                   e/r.sub.-- data.sub.-- group.sub.-- id                                                     ::= Binary(1) 02                                                   tmpl.sub.-- id                                                                             ::= Binary(1) 03                                                   temp.sub.-- tmpl.sub.-- key.sub.-- id                                                      ::= Binary(1) 04                                                   tmpl.sub.-- key.sub.-- id                                                                  ::= Binary(1) 05                                                   field.sub.-- id                                                                            ::= Binary(1) 06                                                   rel.sub.-- id                                                                              ::= Binary(1) 07                                                   orel.sub.-- id                                                                             ::= Binary(1) 08                                                   relent.sub.-- key.sub.-- id                                                                ::= Binary(1) 09                                                   relrel.sub.-- key.sub.-- id                                                                ::= Binary(1) 10                                                   fun.sub.-- parm.sub.-- id                                                                  ::= Binary(1) 11                                                   file.sub.-- data.sub.-- group.sub.-- id                                                    ::= Binary(1) 13                                                   line.sub.-- id                                                                             ::= Binary(1) 14                                                   template.sub.-- name                                                                       ::= Char(8) - Name of entity template                              unique.sub.-- key                                                                          ::= Char(10) - A temporary unique identifier for an entity                     whose key has                                                                   not yet been generated by the repository, or a relationship                   instance.                                                                       Allowable characters are 0-9, the associated interger value                   must                                                                            be greater than zero.                                             key.sub.-- value                                                                           ::= Char(*) - Value of the key                                     field.sub.-- name                                                                          ::= Char(8) - Name of a template field                             field.sub.-- value                                                                         ::= Char(*) - Value of the field                                   fun.sub.-- name                                                                            ::= Char(8) - Name of the function being invoked                   fun.sub.-- parm.sub.-- name                                                                ::= Char(8) - Name of a function parameter                         fun.sub.-- parm.sub.-- value                                                               ::= Char(*) - Value of a function parameter                        line.sub.-- value                                                                          ::= Char(*) - Value of a line in a flat file                       __________________________________________________________________________

BUILDER

The purpose of the Builder function is to build the CDF data stream one unit at a time. The units are built as specified by the FUNCTION₋₋ ID passed in. This function ensures that the CDF data stream being built is valid: if the unit built is invalid, an appropriate return code is passed back to the caller.

The following is the interface to the builder:

    ______________________________________                                         int egppb100(                                                                   unsigned short function.sub.-- id,                                                            IN:      Function to perform                                    short id,      IN:      Unit's id                                              short action,  IN:      Unit's action                                          UNITDATA *data,                                                                               IN:      Unit's name, key, value                                char *filename,                                                                               IN:      File Name                                              char **memptr, INOUT:   Ptr to block of memory                                 B.sub.-- HNDL *handle,                                                                        INOUT:   Ptr to private data area                               char *cc)      OUT:     Reason code                                           ______________________________________                                    

Note: Data types UNITDATA and B₋₋ HNDL are defined in the EGPBACDF H file. You must include this H file in your function that calls the BUILDER.

The purpose of this function is to build a CDF data stream one unit at a time. A unit is defined as an id, action, and data. A unit may be nested to contain other units. To build a nested structure, add the parent unit first, and then all of its dependents. The Builder has functions that work together to build a Common Data Format Data Stream, as well as functions that write the structure to memory or a file. The functions are as follows:

    __________________________________________________________________________     FIRST   Adds the first unit to the CDF Data Stream. This function is only              issued once                                                                    during the Building of a CDF data stream. The unit that                        accompanies the                                                                FIRST Build action only has an ID (i.e., there is no action and                no associated                                                                  data). Following is a list of the allowable units with which the               FIRST function                                                                 may be associated:                                                             EDMM       Adds an EDMM Data Stream unit to the Common Data                    Data Stream                                                                               Format Data Stream                                                             id   EDMM .sub.-- DATA.sub.-- STREAM.sub.-- ID                                 action                                                                              NONE                                                                      data NULL (ignored)                                                            filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              ER Data    Adds an ER.sub.-- Data Group unit to the Common Data                           Format                                                              Group      Data Stream                                                                    id   ER.sub.-- DATA.sub.-- GROUP.sub.-- ID                                     action                                                                              NONE                                                                      data NULL (ignored)                                                            filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              File Data  Adds a File Data Group unit to the Common Data Format               Group      Data Stream                                                                    id   file.sub.-- data.sub.-- group                                             action                                                                              NONE                                                                      data NULL (ignored)                                                            filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                      NEXT    Adds an additional unit. This unit contains an id, action, and                 data portion. If                                                               the Unit is a nesting unit, there may or may not be a data                     portion. Following is                                                          a list of the allowable units with which the Build's NEXT                      function may be                                                                associated:                                                                    Function Call                                                                             Adds a function call to the Common Data Format Data                            Stream                                                                         id   FUN.sub.-- CALL.sub.-- ID                                                 action                                                                              NONE                                                                      data  name = fun.sub.-- name                                                         value = NULL (ignored)                                                         temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              Function Parm                                                                             Adds a function parameter unit to the Common Data                              Format Data Stream                                                             id   FUN.sub.-- PARM.sub.-- ID                                                 action                                                                              NONE                                                                      data  name = fun.sub.-- parm.sub.-- name                                             value = fun.sub.-- parm.sub.-- value                                           temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              ER Data    Adds an ER.sub.-- Data.sub.-- group unit to the Common                         Data Format                                                         Group      Data Stream                                                                    id   ER.sub.-- DATA.sub.-- GROUP.sub.-- ID                                     action                                                                              NONE                                                                      data NULL (ignored)                                                            filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              Template   Adds a template unit to the Common Data Format Data                            Stream                                                                         id   TMPL.sub.-- ID                                                            action                                                                               CREATE                                                                         READ                                                                           UPDATE                                                                         DELETE                                                                   data  name = template.sub.-- name                                                    value = NULL (ignored)                                                         temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              Template Key                                                                              Adds a template key unit to the Common Data Format                             Data Stream. There are two allowable variations.                               id   TEMP.sub.-- TMPL.sub.-- KEY.sub.-- ID                                     action                                                                              NONE                                                                      data  name = NULL (ignored)                                                          value = NULL (ignored)                                                         temp.sub.-- key = temp.sub.-- key                                              rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                                         OR                                                                             id   TEMP.sub.-- KEY.sub.-- ID                                                 action                                                                              NONE                                                                      data  name = NULL (ignored)                                                          value = key.sub.-- value                                                       temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              Field      Adds a field unit to the Common Data Format Data                               Stream                                                                         id   FIELD.sub.-- ID                                                           action                                                                               CREATE                                                                         READ                                                                           UPDATE                                                                         DELETE                                                                   data  name = field.sub.-- name                                                       value = field.sub.-- value                                                     temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              Rel        Adds a relationship unit to the Common Data Format                             Data                                                                           Stream. There are two allowable variations.                                    id   REL.sub.-- ID                                                             action                                                                               CREATE                                                                         READ                                                                           UPDATE                                                                         DELETE                                                                   data  name = NULL (ignored)                                                          value = NULL (ignored)                                                         temp.sub.-- key = rel.sub.-- key                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                                         OR                                                                             id   OREL.sub.-- ID                                                            action                                                                               CREATE                                                                         UPDATE                                                                   data  name = NULL (ignored)                                                          value = NULL (ignored)                                                         temp.sub.-- key = rel.sub.-- key                                               rel.sub.-- posn = rel.sub.-- posn                                        filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              relent key Adds a relationship's source/target entity instance                            key to the                                                                     Common Data Format Data Stream                                                 id   RELENT.sub.-- KEY.sub.-- ID                                               action                                                                              NONE                                                                      data  name = template.sub.-- name                                                    value = NULL (ignored)                                                         temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              relrel key Adds a relationship's source/target relationship                               instance key                                                                   to the Common Data Format Data Stream                                          id   RELREL.sub.-- KEY.sub.-- ID                                               action                                                                              NONE                                                                      data  name = NULL (ignored)                                                          value = NULL (ignored)                                                         temp.sub.-- key = rel.sub.-- key                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              file data group                                                                           Adds a file data group unit to the Common Data Format                          Data Stream                                                                    id   FILE.sub.-- DATA.sub.-- GROUP.sub.-- ID                                   action                                                                              NONE                                                                      data NULL (ignored)                                                            filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                              line       Adds a line unit to the Common Data Format Data                                Stream.                                                                        id   LINE.sub.-- ID                                                            action                                                                              NONE                                                                      data  name = NULL (ignored)                                                          value = line.sub.-- value                                                      temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                                         filename                                                                            NULL (ignored)                                                            memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                      ADD.sub.-- STREAM  Adds a complete, self-contained CDF data stream to the                         current data stream.                                                           The complete self contained data stream must have been                         built using the Builder.                                                       This unit contains the complete unit in a block of                             memory. The block of                                                           memory has all the lenghts, and nested units resolved.                         No semantic checking will                                                      be performed on the units contained within this unit                           block. However, semantic                                                       checks will be performed to see if this unit is                                inserted in the current CDF data                                               stream in the proper context.                                                   The ADD.sub.-- STREAM action can be used with the                             following units. Note:                                                         Memptr and filename are mutually exclusive and                                 required. One or the other must                                                have a value, but not both.                                         er data group                                                                             Adds a complete self-contained ER Data Group unit to                           the                                                                            EMDD Data Stream                                                               id    NO.sub.-- ID (ignored)                                                   action                                                                               NONE                                                                     data  NULL (ignored)                                                           filename                                                                            NULL or file name or er.sub.-- data.sub.-- group                               data stream                                                                    to be inserted                                                            memptr                                                                              NULL or pointer to er.sub.-- data.sub.-- group                                 data stream to                                                                 be inserted                                                               handle                                                                              Handle to Builder's Control Block                              file data group                                                                           Adds a complete self-contained File Data Group unit to                         the                                                                            EDMM Data Stream.                                                              id    NO.sub.-- ID (ignored)                                                   action                                                                               NONE                                                                     action                                                                              NONE                                                                      data NULL (ignored)                                                            filename                                                                            NULL or file name of file.sub.-- data.sub.--                                   group data stream                                                              to be inserted                                                            memptr                                                                              NULL or pointer to file.sub.-- data.sub.-- group                               data stream to                                                                 be inserted                                                               handle                                                                              Handle to Builder's Control Block                      ABNORMAL.sub.-- END                                                                               Caller is requesting an abnormal end to the build                              process before the end of                                                      the data stream has been reached. The Builder function                         dumps and CDF data                                                             already created into a diagnostic file.                                        id    NO.sub.-- ID (ignored)                                                   action                                                                               NONE (ignored)                                                           data  NULL (ignored)                                                           filename                                                                              NULL (ignored)                                                          memptr                                                                              Ignored on input. Data Stream.                                            handle                                                                              Handle to Builder's Control Block                      WRITE.sub.-- MEM   Writes the Common Data Format Data Stream to one                               contiguous block of                                                            memory and returns the address. Memory is allocated by                         the builder. This                                                              function can only be successfully executed once for                            each Common Data Format                                                        Data Stream. After this call has been made, there are                          no other valid calls to the                                                    Builder that reference the current CDF data stream.                            id    NO.sub.-- ID (ignored)                                                   action                                                                               NONE (ignored)                                                           data  NULL (ignored)                                                           filename                                                                             NULL (ignored)                                                           memptr                                                                              Ignored on input. Data Stream.                                            handle                                                                              Handle to Builder's Control Block                      WRITE.sub.-- FILE  Writes the Common Data Format Data Stream to a file.                           The Builder opens the                                                          file, writes the Common Data Format Data Stream to the                         file, and closes the file.                                                     The file's name is specified by the caller by the                              filename input parameter. This                                                 function can only be successfully executed once for                            each Common Data Format                                                        Data Stream. After this call has been made, there are                          no other valid calls to the                                                    Builder that reference the current CDF data stream.                            id    NO.sub.-- ID (ignored)                                                   action                                                                               NONE (ignored)                                                           data NULL (ignored)                                                            filename                                                                            Name of the file to which the Builder writes the                               Common Data                                                                    Format Data Stream.                                                       memptr                                                                              NULL (ignored)                                                            handle                                                                              Handle to Builder's Control Block                      __________________________________________________________________________

Parser

The purpose of the Parser function is to retrieve data one unit at a time from a CDF data stream. The data stream is parsed as specified by the FUNCTION₋₋ HD passed in. During parsing, this function ensures that the CDF data stream is valid; if the unit parsed is invalid, an appropriate return code is passed back to the caller.

The invocation of the Parser function is as follows:

    ______________________________________                                                 sc = egppp100 (function.sub.-- id),                                                cdf.sub.-- file,                                                               &cdf.sub.-- mem,                                                               &handle,                                                                       &id,                                                                           &action,                                                                       &data,                                                                         cc);                                                               ______________________________________                                    

Note: The equivalent function, egphp 100 c, exists on the host for users of EDMM.

Return codes are passed back in the SC and CC fields.

Given a CDF data stream and a specific function to perform, the parser accomplishes the specified task against the CDF data stream. In some cases, a unit of data is returned to the caller. The callable interface is:

    ______________________________________                                         int egppp100(                                                                           unsigned short function.sub.-- id,                                                              IN: Function to                                                                perform                                                       char *filename,  IN: Name of file                                                               with CDF data                                                 char **memptr,   INOUT: Ptr to CDF                                                              data in memory                                                P.sub.-- HNDL *handle,                                                                          INOUT: Ptr to                                                                  persistent data                                               short *id,       OUT: Parsed unit's id                                         short *action,   OUT: Parsed unit's                                                             action                                                        UNITDATA *data,  OUT: Parsed unit's                                                             data                                                          char *cc)        OUT: Condition code                                  ______________________________________                                    

The UNITDATA data type is defined in the EGPBACDF Header file. The UNITDATA type further defines the kinds of data that can be returned for a CDF unit; depending upon the type of unit parsed, its data portion will be in certain field of this structure as specified in the Header file. This Header file must be included in any function that interacts with the CDF data stream in any way.

The purpose of this function is to parse a CDF data stream one unit at a time. A CDF unit is defined as having a length, id, action, and sometimes data. All but the length of the unit is returned to the caller from the Parser function. A unit may be nested to contain other units. When parsing, the caller receives units in the order they occur in the CDF data stream. Thus, the "nesting" unit is parsed before its nested "children" units. The caller has the option to skip these parent nesting units should that unit type not make sense to them.

In addition to simply parsing units from the data stream, the Parser also verifies the semantic correctness of the data stream at each step through parsing. If at any point during the parsing process the unit is invalid with respect to the unit previously parsed, or the unit's action is invalid for the particular unit, the parsing process terminates with an appropriate condition code to alert the caller of an invalid data stream.

When the Parser function reaches the end of the data stream, or when an ABNORMAL₋₋ END function is specified, a warning code accompanied by an EOF condition code is returned to the caller.

The Parser function is intended to provide a complete package of functions that can be executed against the given CDF data stream. The functions and their descriptions are as follows:

    __________________________________________________________________________     FIRST    Parse the first CDF unit from the data stream. This function is                only issued                                                                    once during the parsing of a CDF data stream. The only units the               caller                                                                         can expect from a FIRST call appear below. These units are the                 "header"                                                                       units in the data stream. Their actions are always NONE and they               have no                                                                        data. If any other units appears first in the data stream, the                 Parser terminates                                                              with an "invalid data stream" condition code. Following is a                   list of the                                                                    input and output data associated with a FIRST call:                            Edmm Data Stream                                                                         The Common Data Format Data Stream being parsed                                may contain Function, E/R, and File data.                                      function.sub.-- id                                                                    FIRST                                                                   filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data stream in memory                                    handle Pointer to Parser's persistent data control                                    block                                                                   id     EDMM.sub.-- DATA.sub.-- STREAM.sub.-- ID                                action NONE                                                                    data   NULL (fields in structure are empty)                          E/R Data Group                                                                           The Common Data Format Data Stream being parsed                                contains E/R data                                                              function.sub.-- id                                                                    FIRST                                                                   filename                                                                              Name of file containing CDF data stream                                        (opened by Parser)                                                      memptr Pointer to CDF data stream in memory                                           (updated as stream is parsed)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     ER.sub.-- DATA.sub.-- GROUP.sub.-- ID                                   action NONE                                                                    data   NULL (fields in structure are empty)                          File Data Group                                                                          The Common Data Format Data Stream being parsed                                contains File data                                                             function.sub.-- id                                                                    FIRST                                                                   filename                                                                              Name of file containing CDF data stream                                        (opened by Parser)                                                      memptr Pointer to CDF data stream in memory                                           (updated as stream is parsed)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     FILE.sub.-- DATA.sub.-- GROUP.sub.-- ID                                 action NONE                                                                    data   NULL (fields in structure are empty)                 NEXT     Parse the next unit from the CDF data stream. This function                    presumes that                                                                  a position has already been established in the stream via the                  FIRST                                                                          function. If positioning has not already been established, the                 Parser returns                                                                 with an error, but the user has the ability to then issue a                    FIRST to correct                                                               the problem. The unit returned contains an id, action, and data                portion, if                                                                    data exists for that unit. Following is a list of the input and                output data                                                                    associated with a Parser NEXT function:                                        Function Call                                                                            The CDF data stream contains a function call data                              function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     FUN.sub.-- CALL.sub.-- ID                                               action NONE                                                                    data                                                                                  name = fun.sub.-- name                                                         value = NULL (empty)                                                           temp.sub.-- key = NULL (empty)                                                 rel.sub.-- posn = NULL (empty)                                Function Parameter                                                                       Function Call data in data stream contains function                            parameter data                                                                 function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     FUN.sub.-- PARM.sub.-- ID                                               action NONE                                                                    data                                                                                  name = fun.sub.-- parm.sub.-- name                                             value = fun.sub.-- parm.sub.-- value                                           temp.sub.-- key = NULL (ignored)                                               rel.sub.-- posn = NULL (ignored)                              ER Data Group                                                                            The CDF data stream contains E/R data                                          function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     ER.sub.-- DATA.sub.-- GROUP.sub.-- ID                                   action NONE                                                                    data   NULL (empty)                                                  Template  E/R data in data stream contains template instance                             function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     TEMPL.sub.-- ID                                                         action                                                                                CREATE                                                                         READ                                                                           UPDATE                                                                         DELETE                                                                  data                                                                                  name = template.sub.-- name                                                    value = NULL (empty)                                                           temp.sub.-- key = NULL (empty)                                                 rel.sub.-- posn = NULL (empty)                                Template Key                                                                             Template instance in data stream contains template                             key                                                                            (temporary or real)                                                            function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     TEMP.sub.-- TMPL.sub.-- KEY.sub.-- ID                                   action NONE                                                                    data                                                                                  name = NULL (empty)                                                            value = NULL (empty)                                                           temp.sub.-- key = temp.sub.-- key -                                            rel.sub.-- posn = NULL (empty)                                          OR                                                                             function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     TMPL.sub.-- KEY.sub.-- ID                                               action NONE                                                                    data                                                                                  name = NULL (empty)                                                            value = key.sub.-- value                                                       temp.sub.-- key = NULL (empty)                                                 rel.sub.-- posn = NULL (empty)                                Field     Template instance in data stream contains field                                function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     FIELD.sub.-- ID                                                         action                                                                                CREATE                                                                         READ                                                                           UPDATE                                                                         DELETE                                                                  data                                                                                  name = field.sub.-- name                                                       value = field.sub.-- value                                                     temp.sub.-- key = NULL (empty)                                                 rel.sub.-- posn = NULL (empty)                                Rel       E/R data in data stream contains relationship                                  instance                                                                       (two allowable variations)                                                     function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     REL.sub.-- ID                                                           action                                                                                CREATE                                                                         READ                                                                           DELETE                                                                  data                                                                                  name = NULL (empty)                                                            value = NULL (empty)                                                           temp.sub.-- key = rel.sub.-- key                                               rel.sub.-- posn = NULL (empty)                                          OR                                                                             function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     OREL.sub.-- ID                                                          action                                                                                CREATE                                                                         UPDATE                                                                  data                                                                                  name = NULL (empty)                                                            value = NULL (empty)                                                           temp.sub.-- key = rel.sub.-- key                                               rel.sub.-- posn = rel.sub.-- posn                             relent key                                                                               Relationship in data stream has source/target that is                          entity instance                                                                function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     RELENT.sub.-- KEY.sub.-- ID                                             action NONE                                                                    data                                                                                  name = template.sub.-- name                                                    value = NULL (empty)                                                           temp.sub.-- key = NULL (empty)                                                 rel.sub.-- posn = NULL (empty)                                relrel key                                                                               Relationship in data stream has source/target that is                          relationship instance                                                          function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     RELREL.sub.-- KEY.sub.-- ID                                             action NONE                                                                    data                                                                                  name = NULL (empty)                                                            value = NULL (empty)                                                           temp.sub.-- key = rel.sub.-- key                                               rel.sub.-- posn = NULL (empty)                                file data group                                                                          The CDF data stream contains file data                                         function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     FILE.sub.-- DATA.sub.-- GROUP.sub.-- ID                                 action NONE                                                                    data   NULL (empty)                                                  line      File data in data stream contains line data                                    function.sub.-- id                                                                    NEXT                                                                    filename                                                                              Name of file containing CDF data stream                                 memptr Pointer to CDF data in memory                                                  (updated from previous parse)                                           handle Pointer to Parser's persistent data control                                    block                                                                   id     LINE.sub.-- ID                                                          action NONE                                                                    data                                                                                  name = NULL (empty)                                                            value = line.sub.-- value                                                      temp.sub.-- key = NULL (empty)                                                 rel.sub.-- posn = NULL (empty)                       PREVIOUS Return unit data for previous unit parsed from CDF data stream.                This                                                                           function presumes that a position has already been established                 in the stream                                                                  via a FIRST function. If positioning has not already been                      established, the                                                               Parser returns with an error, but the user has the ability to                  then issue a                                                                   FIRST to correct the problem. The unit returned is the unit that               has JUST                                                                       been parsed; that is, the caller can only go back ONE unit. The                unit                                                                           returned contains an id, action, and data portion, if data                     exists for that unit.                                                          Any unit may be returned as a result of the Parser PREVIOUS                    function.                                                                      Refer to the lists of units for FIRST or NEXT for the complete                 list.                                                                 SKIP     Skips the unit previously parsed from the CDF data stream.                     Again, this                                                                    function presumes that a position has already been established                 in the stream                                                                  via a FIRST function. This function does not return any unit                   data. Rather,                                                                  it simply skips the unit that has JUST been parsed; successive                 SKIP calls to                                                                  the Parser do NOT result in several units being skipped, but                   only succeed in                                                                skipping the same unit over and over. A SKIP call can be used to               skip an                                                                        entire nested unit of CDF data or a single unit of data                        (although skipping a                                                           single unit is an effective no-op).                                   GET.sub.-- STREAM                                                                       Copy the PREVIOUS unit parsed (including all of its imbedded                   units) into a                                                                  separate file or memory location as specified by the caller.                   This call is                                                                   issued when the caller has passed as ER.sub.-- DATA.sub.-- GROUP               or                                                                             FILE.sub.-- DATA.sub.-- GROUP unit and wants the entire E/R Data               Group of File                                                                  Data Group data stream imbedded within the CDF stream being                    parsed to                                                                      be placed in a separate location for later access. The original                data stream is                                                                 not changed; the E/R or File data being copied is SKIPped in the               original                                                                       data stream so that parsing resumes at the unit following that                 imbedded                                                                       stream.                                                                        The GET.sub.-- STREAM function cannot be issued on any units                   other                                                                          than E/R.sub.-- DATA.sub.-- GROUP and FILE.sub.-- DATA.sub.--                  GROUP and these units must                                                     have first been parsed by the caller. An attempt to issue                      GET.sub.-- STREAM on                                                           any other unit results in an error and the Parser will                         terminate.                                                                     Possible values sent to and returned from the Parser for                       GET.sub.-- STREAM are:                                                         E/R Data Group                                                                           The E/R Data Group, complete with imbedded                                     template and relationship data, is copied from the                             CDF                                                                            data stream being parsed.                                            (IN) function.sub.-- id                                                                  GET.sub.-- STREAM                                                    (IN) filename                                                                            Name of the file which is to contain copied                                    E/R Data Group data stream (NULL if data                                       is to be copied to memory)                                           (IN/OUT) memptr                                                                          Ignored upon input. Upon output                                                and if filename is not specified, location in                                  memory of E/R Data Group copied                                      handle    Pointer to Parser's persistent data control block                    id        ER.sub.-- DATA.sub.-- GROUP.sub.-- ID                                action    NONE                                                                 data      NULL (fields in structure are empty)                                           A subsequent NEXT on the original data                                         stream yields the unit immediately following the                               entire                                                                         E/R Data Group.                                                      File Data Group                                                                          The File Data Group, complete with imbedded lines, is                          copied from the CDF data stream being parsed.                                  (IN) function.sub.-- id                                                                  GET.sub.-- STREAM                                                    (IN) filename                                                                            Name of the file which is to contain copied                                    File Data Group data stream (NULL if data                                      is to be copied to memory)                                           (IN/OUT) memptr                                                                          Ignored upon input. Upon output                                                and if filename is not specified, location                                     in                                                                             memory of File Data Group copied                                     handle    Pointer to Parser's persistent data control                                    block                                                                id        FILE.sub.-- DATA.sub.-- GROUP.sub.-- ID                              action    NONE                                                                 data      NULL (fields in structure are empty)                                 A subsequent NEXT on the original data                                         stream yields the unit immediately following the                               entire                                                                         E/R Data Group.                                             ABNORMAL.sub.-- END                                                                       Alerts Parser function that caller has experienced problem and                 that parsing                                                                   is to be terminated on the CDF data stream currently being                     parsed. When                                                                   this function is specified, the Parser does the necessary work                 to clean up all                                                                temporary and persistent data used during parsing. This                        enables the parsing                                                            process to begin cleanly for the same calling function on a                    new data stream.                                                               (Note: the processing done for this function is exactly the                    same as when the                                                               Parser reaches the end of the CDF data stream.)                     Free CDF Function                                                              The purpose of the Free CDF function is to discard CDF data stream             memory.                                                                        Free CDF interface:                                                            (In) CDF.sub.-- MEM                                                                      char*                                                                Parameters                                                                              Descriptions                                                          CDF.sub.-- MEM                                                                          Pointer to CDF data in memory.                                        The invocation of the Free CDF function is as follows:                         char *cdf.sub.-- mem;                                                          short sc;                                                                      . . .                                                                          egppafre (cdf.sub.-- mem);                                                     Note: The equivalent function, egphafre c, exists on the host for users        of EDMM.                                                                       __________________________________________________________________________

EDMM Communication Facility

The purpose of the EDMM Communication Facility is to enable a work station application to invoke a fully-integrated Repository Manager MVS function on the host communicating all file and E/R data between the work station and host functions. The communication is achieved by an open/close Repository Manager/MVS function that opens the Repository Manager, transfers the function interface, file, and E/R data to the host in a CDF data stream, invokes the host fully-integrated RM host function specified in the data stream, returns the function interface and all data associated with the function call in a CDF data stream to the work station, and closes the Repository Manager/MVS. If no errors are encountered, output parameters and data, if any, for the host function, are returned to the caller in a CDF data stream.

    ______________________________________                                         Interface                                                                      ______________________________________                                         EDMM Communication Facility Interface                                          (In) CDF.sub.-- FILE       char 47                                             (In/Out) CDF.sub.-- MEM    char *                                              (Out) SC                   short                                               (Out) CC                   char 9                                              Parameters                                                                              Descriptions                                                          CDF.sub.-- FILE                                                                         Name of work station file containing CDF data                                  stream. (Opened and closed in this function.)                                  CDF.sub.-- FILE and CDF.sub.-- MEM are mutually                                exclusive. See the description of CDF.sub.-- MEM for                           more information about CDF data stream content.                                When the EDMM Communication Facility returns                                   control to the caller, the output CDF data stream                              will usually be in memory (i.e., pointed to by                                 CDF.sub.-- MEM). However, if suffient memory is not                            available, the CDF data stream will be written to                              a file, and CDF.sub.-- MEM will return a NULL value.                           As curently implemented, the output CDF file is                                allocated within this function and the name is hard-                           coded as EGPPTCDF.OUT.                                                CDF.sub.-- MEM                                                                          Work station address of CDF data stream in                                     memory. CDF.sub.-- FILE and CDF.sub.-- MEM are                                 mutually exclusive: The caller of this function will                           use the Builder to create a CDF data stream that                               contains information on the function to be invoked                             on the host and its parameters, possibly including                             an imbedded CDF data stream containing file or                                 E/R data units.                                                                As an output parameter, CDF.sub.-- MEM points to a                             CDF data stream that contains output parameters                                returned by the host function that was invoked on                              behalf of the caller. Again, depending on the host                             function interface, the CDF data stream may also                               include an imbedded CDF data stream containing                                 file or E/R data units.                                                        The caller will use the Parser to retrieve this                                information from the CDF data stream.                                 SC       Return code representing processing results                           CC       Condition code representing processing results                        ______________________________________                                    

The invocation of the EDMM Communication Facility is as follows: ##EQU1## Return codes are passed back in the CC and SC fields.

Productivity Facility

The Productivity Facility (PF) is the component that

enables the rapid creation of data manipulation facilities based on a variety of views of E/R data in the repository and

customizes the Communication Facility function.

The PF creates Repository Manager C-Language functions described below.

Load BB: A function that interprets a CDF data stream containing entity, attribute, and relationship information. It updates the repository as specified by the action field of each CDF unit.

Unload BB: A function that retrieves a group of connected entities and relationships from the repository and translates the entity, attribute, and relationship information via the Builder function into a CDF data stream.

Copy BB: A function that copies a group of connected entity and relationship instances in the repository.

Delete BB: A function that deletes a group of connected entity and relationship instances from the repository.

Communication Facility: The host portion of CF that enables the function routing to your RM functions.

Load BB

The Load₋₋ BB function adds or updates a logical unit of data in the repository as specified by the CDF data stream. Data is passed in as template and relationship units in an ER data group.

Separate functions must be defined for each data view needed by the application (i.e. each different template tree).

Note: Currently this function does not obtain any locks or perform any commits. In situations where the data must be locked before update, a lock must be separately obtained on the necessary entity instance prior to invoking the load function. A Commit should be performed after invoking this function in order to make changes to the repository permanent.

    ______________________________________                                         Interface                                                                      ______________________________________                                         Load.sub.-- BB Interface                                                       (In) CDF.sub.-- MEM        Fixed   32                                          (In) CDF.sub.-- FILE       Char    46                                          (Out) SC                   Fixed   16                                          (Out) CC                   Char     8                                          Parameters                                                                              Descriptions                                                          CDF.sub.-- MEM                                                                          Host memory location of CDF data stream con-                                   taining E/R data to be added, deleted, or updated                              in the repository. Caller will use the Builder                                 function to put data to be loaded in a                                         CDF data stream.                                                               Note: CDF.sub.-- MEM and CDF.sub.-- FILE are mutually                          exclusive.                                                            CDF.sub.-- FILE                                                                         Host file containing CDF data stream                                  SC       Severity code reflecting processing results                           CC       Condition code reflecting processing results                          ______________________________________                                    

Return codes are passed back in the CS and CC fields of the data stream. Since the Load₋₋ BB functions are generated, each Load₋₋ BB has the same set of possible return codes.

Unload₋₋ BB

The Unload₋₋ BB function retrieves a logical unit of data from the repository and puts it in CDF data stream. Data is returned as template and relationship units in an ER data group.

Separate functions must be defined for each data view needed by the application (i.e. each different template tree).

Note: Currently this function does not obtain any locks. To avoid a "dirty read" a lock must be obtained on the aggregation instance.

    ______________________________________                                         Interface                                                                      ______________________________________                                         Unload.sub.-- BB Interface                                                     ______________________________________                                         (In) SYSKEY      Fixed        31                                               (Out) CDF.sub.-- MEM                                                                            Fixed        32                                               (Out) CDF.sub.-- FILE                                                                           Char         46                                               (Out) SC         Fixed        16                                               (Out) CC         Char          8                                               ______________________________________                                         Parameters                                                                              Descriptions                                                          ______________________________________                                         SYSKEY   System-assigned key of the aggregation instance                                to be unloaded.                                                       CDF.sub.-- MEM                                                                          Host memory location of CDF data stream                                        containing the E/R data retrieved from the                                     repository. Caller will use the Parser function                                to extract the data from the CDF data stream.                                  Note: CDF.sub.-- MEM and CDF.sub.-- FILE are mutually                          exclusive.                                                            CDF.sub.-- FILE                                                                         Host file name of CDF data stream containing the                               E/R data retrieved from the repository.                                        Caller will use the Parser function to extract the                             data from the CDF data stream.                                        SC       Severity code reflecting processing results                           CC       Condition code reflecting processing results                          ______________________________________                                    

Host Function Invocation

Return codes are passed back in the CS and CC fields of the data stream. Since the Unload₋₋ BB functions are generated, each Unload₋₋ BB has the same set of possible return codes.

Copy₋₋ BB

The purpose of the Copy₋₋ BB function is to allow the user to copy an entire object in the repository, storing the duplicate under another name. Any data view (i.e. a template tree) can can be copied using this function. The target of the Copy₋₋ BB must not already exist. The Copy₋₋ BB functions do not copy shareable subcomponents, but will create relationships to the shared subcomponents.

Note: As used herein all objects and shareable subcomponents have a root template with the following attributes: name, qualifier, and level. This function and its interface will have to be modified the data view does not conform to this naming standard.

Note: Currently this function does not obtain any locks or perform any commits. To avoid a "dirty read" a lock must be obtained on the source aggregation instance. A Commit should be performed after invoking this function in order to make changes to the repository permanent, obtained to avoid a "dirty read".

    ______________________________________                                         Interface                                                                      ______________________________________                                         Copy.sub.-- BB Interface                                                       ______________________________________                                         (In) SYSKEY      Fixed        31                                               (In) TRG.sub.-- NAME                                                                            Char         32                                               (In) TRG.sub.-- QLFR                                                                            Char          8                                               (In) TRG.sub.-- LVL                                                                             Char          2                                               (Out) SC         Fixed        16                                               (Out) CC         Char          8                                               ______________________________________                                         Parameters                                                                               Descriptions                                                         ______________________________________                                         SYSKEY    System-assigned key of the aggregation                                         instance to be copied.                                               TRG.sub.-- NAME                                                                          Name of target aggregation instance                                  TRG.sub.-- QLFR                                                                          Qualifier of target aggregation instance                             TRG.sub.-- LVL                                                                           Level of target aggregation instance                                 SC        Severity code reflecting processing results                          CC        Condition code reflecting proccssing results                         ______________________________________                                    

Return codes are passed back in the SC and CC fields of the data stream. Since the Copy₋₋ BB functions are generated, each Copy₋₋ BB has the same set of possible return codes.

Delete₋₋ BB

The purpose of the Delete₋₋ BB function is to enable the user to delete an object instance from the repository. This function can delete any data view (i.e. template tree). The Delete₋₋ BB functions defined here do not delete shareable subcomponents, but will delete the relationships to the shared subcomponents. The Load function can be used to delete individual entity instances within an aggregation instance.

Note: Currently this function does not obtain any locks or perform any commits. A DELETE lock must be obtained on the aggregation instance before invoking the function. A Commit should be performed after invoking this function in order to make the delete permanent.

    ______________________________________                                         Interface                                                                      ______________________________________                                         Delete.sub.-- BB Interface                                                     ______________________________________                                         (In) SYSKEY      Fixed        31                                               (Out) SC         Fixed        16                                               (Out) CC         Char          8                                               ______________________________________                                         Parameters                                                                              Descriptions                                                          ______________________________________                                         SYSKEY   System-assigned key of the aggregation instance                                to be deleted.                                                        SC       Severity code reflecting processing results                           CC       Condition code reflecting processing results                          ______________________________________                                    

Return codes are passed back in the SC and CC fields of the data stream. Since the Delete₋₋ BB functions are generated, each Delete₋₋ BB has the same set of possible return codes.

Builder-Parser State Tables

Documented below is a state table that describes the valid units and actions when parsing or building a CDF data stream.

                                      TABLE 1                                      __________________________________________________________________________     EDMM Builder/Parser State Table                                                                        Next                                                   State                                                                             CDF Unit/Builder/Parser Action                                                                      State                                                                             Description                                         __________________________________________________________________________     0  EDMM.sub.-- DATA.sub.-- STREAM/FIRST                                                                1  Initial Start State.                                   ER.sub.-- DATA.sub.-- GROUP/FIRST                                                                   24                                                        FILE.sub.-- DATA.sub.-- GROUP/FIRST                                                                 31                                                     1  FUN.sub.-- CALL/NEXT 2  Processing an                                          EDMM.sub.-- DATA.sub.-- STREAM/SKIP                                                                 0  edmm.sub.-- data.sub.-- stream.                     2  FUN.sub.-- CALL/NEXT 2  Processing a function call.                            FUN.sub.-- PARM/NEXT 2                                                         ER.sub.-- DATA.sub.-- GROUP/NEXT                                                                    3                                                         ER.sub.-- DATA.sub.-- GROUP/ADD.sub.-- STREAM                                                       25                                                        FUN.sub.-- CALL/SKIP 26                                                        FILE.sub.-- DATA.sub.-- GROUP/NEXT                                                                  33                                                        FILE.sub.-- DATA.sub.-- GROUP/ADD.sub.-- STREAM                                                     35                                                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      3  TMPL/NEXT            4  Processing an er.sub.-- data.sub.-- group              REL/NEXT             7  that is paired with a                                  OREL/NEXT            36 function.sub.-- call. (Root is an                      ER.sub.-- DATA.sub.-- GROUP/SKIP                                                                    2  edmm.sub.-- data.sub.-- stream)                        ER.sub.-- DATA.sub.-- GROUP/GET.sub.-- STREAM                                                       2                                                      4  TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    5  Processing a template.                                 TMPL.sub.-- KEY/NEXT 5  (Root is an                                            TMPL/SKIP            27 edmm.sub.-- data.sub.-- stream)                     5  FUN.sub.-- CALL/NEXT 2  Processing the a template                              TMPL/NEXT            4  key list of a template. (Root                          TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    5  is an edmm.sub.-- data.sub.-- stream)                  TMPL.sub.-- KEY/NEXT 5                                                         FIELD/NEXT           6                                                         REL/NEXT             7                                                         OREL/NEXT            36                                                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      6  FUN.sub.-- CALL/NEXT 2  Processing a field list of a                           TMPL/NEXT            4  template. (Root is an                                  FIELD/NEXT           6  edmm.sub.-- data.sub.-- stream)                        REL/NEXT             7                                                         OREL/NEXT            36                                                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      7  RELREL.sub.-- KEY/NEXT                                                                              8  Processing a rel. (Root is an                          RELENT.sub.-- KEY/NEXT                                                                              9  edmm.sub.-- data.sub.-- stream)                        REL/SKIP             27                                                     8  RELREL.sub.-- KEY/NEXT                                                                              11 Processing a relrel.sub.-- key                                                 which is the source key of a                           RELENT.sub.-- KEY/NEXT                                                                              12 rel. (Root is an                                                               edmm.sub.-- data.sub.-- stream)                     9  TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    10 Processing a relent.sub.-- key                         TMPL.sub.-- KEY/NEXT 10 which is the source key of a                           RELENT.sub.-- KEY/SKIP                                                                              28 rel. (Root is an                                                               edmm.sub.-- data.sub.-- stream)                     10 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    10 Processing the template key                            TMPL.sub.-- KEY/NEXT 10 list of a relent.sub.-- key. The                       RELREL.sub.-- KEY/NEXT                                                                              11 relent.sub.-- key is the source key                    RELENT.sub.-- KEY/NEXT                                                                              12 of a rel. (Root is an                                                          edmm.sub.-- data.sub.-- stream)                     11 FUN.sub.-- CALL/NEXT 2  Processing a relrel.sub.-- key                         TMPL/NEXT            4  which is the target key of a                           REL/NEXT             7  rel. (Root is an                                       OREL/NEXT            36 edmm.sub.-- data.sub.-- stream)                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      12 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    13 Processing a relent.sub.-- key                         TMPL.sub.-- KEY/NEXT 13 which is the target key of a                           RELENT.sub.-- KEY/SKIP                                                                              27 rel. (Root is an                                                               edmm.sub.-- data.sub.-- stream)                     13 FUN.sub.-- CALL/NEXT 2  Processing the template key                            TMPL/NEXT            4  list of a relent.sub.-- key. The                       REL/NEXT             7  relent.sub.-- key is the target key                    OREL/NEXT            36 of a rel. (Root is an                                  TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    13 edmm.sub.-- data.sub.-- stream)                        TMPL.sub.-- KEY/NEXT 13                                                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      14 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    15 Processing a template.                                 TMPL.sub.-- KEY/NEXT 15 (Root is an er.sub.-- data.sub.-- group)               TMPL/SKIP            29                                                     15 TMPL/NEXT            14 Processing the a template                              TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    15 key list of a template. (Root                          TMPL.sub.-- KEY/NEXT 15 is an er.sub.-- data.sub.-- group)                     FIELD/NEXT           16                                                        REL/NEXT             17                                                        OREL/NEXT            37                                                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      16 TMPL/NEXT            14 Processing a field list of a                           FIELD/NEXT           16 template. (Root is an                                  REL/NEXT             17 er.sub.-- data.sub.-- group)                           OREL/NEXT            37                                                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      17 RELREL.sub.-- KEY/NEXT                                                                              18 Processing a rel. (Root is an                          RELENT.sub.-- KEY/NEXT                                                                              19 er.sub.-- data.sub.-- group)                           REL/SKIP             29                                                     18 RELREL.sub.-- KEY/NEXT                                                                              21 Processing a relrel.sub.-- key                         RELENT.sub.-- KEY/NEXT                                                                              22 which is the source key of a                                                   rel. (Root is an                                                               er.sub.-- data.sub.-- group)                        19 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    20 Processing a relent.sub.-- key                         TMPL.sub.-- KEY/NEXT 20 which is the source key of a                           RELENT.sub.-- KEY/SKIP                                                                              30 rel. (Root is an                                                               er.sub.-- data.sub.-- group)                        20 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    20 Processing the template key                            TMPL.sub.-- KEY/NEXT 20 list of a relent.sub.-- key. The                       RELREL.sub.-- KEY/NEXT                                                                              21 relent.sub.-- key is the source key                    RELENT.sub.-- KEY/NEXT                                                                              22 of a rel. (Root is an                                                          er.sub.-- data.sub.-- group)                        21 TMPL/NEXT            14 Processing of a relrel.sub.-- key                      REL/NEXT             17 which is the target key of a                           OREL/NEXT            37 rel. (Root is an                                       FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0  er.sub.-- data.sub.-- group)                        22 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    23 Processing a relent.sub.-- key                         TMPL.sub.-- KEY/NEXT 23 which is the target key of a                           RELENT.sub.-- KEY/SKIP                                                                              29 rel. (Root is an                                                               er.sub. -- data.sub.-- group)                       23 TMPL/NEXT            14 Processing the template key                            REL/NEXT             17 list of a relent.sub.-- key. The                       OREL/NEXT            37 relent.sub.-- key is the target key                    TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    23 of a rel. (Root is an                                  TMPL.sub.-- KEY/NEXT 23 er.sub.-- data.sub.-- group)                           FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      24 TMPL/NEXT            14 Processing an er.sub.-- data.sub.-- group              REL/NEXT             17 that is root unit.                                     OREL/NEXT            37                                                        ER.sub.-- DATA.sub.-- GROUP/SKIP                                                                    0                                                         ER.sub.-- DATA.sub.-- GROUP/GET.sub.-- STREAM                                                       0                                                      25 FUN.sub.-- CALL/NEXT 2  Processing an er.sub.-- data.sub.-- group              FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0  that is a complete stream.                                                     It is paired with a                                                            function.sub.-- call. (Root is an                                              edmm.sub.-- data.sub.-- stream)                     26 ER.sub.-- DATA.sub.-- GROUP/NEXT                                                                    3  Processing a SKIP to the                               FUN.sub.-- CALL/NEXT 2  end of a function call.                                FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0  (Root is an                                                                    edmm.sub.-- data.sub.-- stream)                     27 FUN.sub.-- CALL/NEXT 2  Processing a SKIP to the                               TMPL/NEXT               end of a template, or                                  REL/NEXT             7  relation unit. (Root is an                             OREL/NEXT            36 edmm.sub.-- data.sub.-- stream)                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      28 RELREL.sub.-- KEY/NEXT                                                                              11 Processing a SKIP to the                               RELENT.sub.-- KEY/NEXT                                                                              12 end of a relent source key of                                                  a rel. (Root is an                                                             edmm.sub.-- data.sub.-- stream)                     29 TMPL/NEXT            14 Processing a SKIP to the                               REL/NEXT             17 end of a template, or                                  OREL/NEXT            37 relation unit. (Root is an                             FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0  er.sub.-- data.sub.-- group)                        30 RELREL.sub.-- KEY/NEXT                                                                              21 Processing a SKIP to the                               RELENT.sub.-- KEY/NEXT                                                                              22 end of relent source key of                                                    a rel. (Root is an                                                             er.sub.-- data.sub.-- group)                        31 FILE.sub.-- DATA.sub.-- GROUP/SKIP                                                                  0  Processing a file.sub.-- data.sub.-- group             FILE.sub.-- DATA.sub.-- GROUP/GET.sub.-- STREAM                                                     0  which is root unit.                                    LINE/NEXT            32                                                     32 LINE/NEXT            32 Processing a line of a                                 FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0  file.sub.-- data.sub.-- group. (Root is a                                      file.sub.-- data.sub.-- group.)                     33 FILE.sub.-- DATA.sub.-- GROUP/SKIP                                                                  2  Processing a                                           FILE.sub.-- DATA.sub.-- GROUP/GET.sub.-- STREAM                                                     2  file.sub.-- data.sub.-- group. It is paired            LINE/NEXT            34 with a function call. (Root                                                    is an edmm.sub.-- data.sub.-- stream)               34 FUN.sub.-- CALL/NEXT 2  Processing a line of a                                 LINE/NEXT            34 file.sub.-- data.sub.-- group. (Root is an             FINAL.sub.-- STATE.sub.-- ID/FINAL STATE                                                            0  edmm.sub.-- data.sub.-- stream)                     35 FUN.sub.-- CALL/NEXT 2  Processing a file.sub.-- data.sub.-- group             FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0  which is a complete stream.                                                    It is paired with a                                                            function.sub.-- call. (Root is an                                              edmm.sub.-- data.sub.-- stream)                     36 RELREL/NEXT          38 Processing an orel. (Root is                           RELENT/NEXT          39 an edmm.sub.-- data.sub.-- stream)                     OREL/SKIP            27                                                     37 RELREL/NEXT          43 Processing an orel. (Root is                           RELENT/NEXT          44 an er.sub.-- data.sub.-- group)                        OREL/SKIP            29                                                     38 RELENT.sub.-- KEY/NEXT                                                                              41 Processing a relrel.sub.-- key                                                 which is the source key of                                                     an orel. (Root is an                                                           edmm.sub.-- data.sub.-- stream)                     39 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    40 Processing a relent.sub.-- key                         TMPL.sub.-- KEY.sub.-- NEXT                                                                         40 which is the source key of                             RELENT.sub.-- KEY/SKIP                                                                              49 an orel. (Root is an                                                           edmm.sub.-- data.sub.-- stream)                     40 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    40 Processing the template key                            TMPL.sub.-- KEY/NEXT 40 list of a relent.sub.-- key. The                       RELENT.sub.-- KEY/NEXT                                                                              41 relent.sub.-- key is the source key                                            of an orel. (Root is an                                                        edmm.sub.-- data.sub.-- stream)                     41 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    42 Processing a relent.sub.-- key                         TMPL.sub.-- KEY/NEXT 42 which is the target key of an                          RELENT.sub.-- KEY/SKIP                                                                              27 orel. (Root is an                                                              edmm.sub.-- data.sub.-- stream)                     42 FUN.sub.-- CALL/NEXT 2  Processing the template key                            TMPL/NEXT            4  list of a relent.sub.-- key. The                       REL/NEXT             7  relent.sub.-- key is the target key                    OREL/NEXT            36 of an orel. (Root is an                                TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    42 edmm.sub.-- data.sub.-- stream)                        TMPL.sub.-- KEY/NEXT 42                                                        FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      43 RELENT.sub.-- KEY/NEXT                                                                              46 Processing a relrel.sub.-- key                                                 which is the source key of                                                     an orel. (Root is an                                                           er.sub.-- data.sub.-- group)                        44 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    45 Processing a relent.sub.-- key                         TMPL.sub.-- KEY/NEXT 45 which is the source key of                             RELENT.sub.-- KEY/SKIP                                                                              48 an orel. (Root is an                                                           er data.sub.-- group)                               45 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    45 Processing the template key                            TMPL.sub.-- KEY/NEXT 45 list of a relent.sub.-- key. The                       RELENT.sub.-- KEY/NEXT                                                                              46 relent.sub.-- key is the source key                                            of an orel. (Root is an                                                        er.sub.-- data.sub.-- group)                        46 TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    47 Processing a relent.sub.-- key                         TMPL.sub.-- KEY/NEXT 47 which is the target key of an                          RELENT.sub.-- KEY/SKIP                                                                              29 orel. (Root is an                                                              er.sub.-- data.sub.-- group)                        47 TMPL/NEXT            14 Processing the template key                            REL/NEXT             17 list of a relent.sub.-- key. The                       OREL/NEXT            317                                                                               relent.sub.-- key is the target key                    TEMP.sub.-- TMPL.sub.-- KEY/NEXT                                                                    47 of an orel. (Root is an                                TMPL.sub.-- KEY/NEXT 47 er.sub.-- data.sub.-- group)                           FINAL.sub.-- STATE.sub.-- ID/FINAL.sub.-- STATE                                                     0                                                      48 RELENT.sub.-- KEY/NEXT                                                                              46 Processing a SKIP to the                                                       end of a relent source key of                                                  an orel. (Root is an                                                           er.sub.-- data.sub.-- group)                        49 RELENT.sub.-- KEY/NEXT                                                                              41 Processing a SKIP to the                                                       end of a relent source key of                                                  an orel. (Root is an                                                           edmm.sub.-- data.sub.-- stream)                     __________________________________________________________________________

PF/Creating Data Handling Functions

To create a data handling function, perform the following steps:

1. From RM select a private tool group as the current tool group.

2. From the main panel of RM enter the option to go to the Logical View (LV).

3. Select the option to make a copy of one of the base data handling functions to your own private function.

If you are creating a Load function put EGPLOAD as the source function name and put the name of the function that you wish to create as the target function name. To create an unload function use EGPUNLD, for copy use EGPCOPY and for delete use EGPDELT for the source function name.

4. After the function has been successfully copied return to the main LV panel and enter the name of the function you just added at the top of the panel.

5. Select the option to specify your function's templates. In each template that you add make sure you add an extra field named REL₋₋ NAME that is CHAR 32 (Varying Length).

6. From the main LV panel select the option to create the connections between your templates. (Note: Your template tree can only have one root).

7. From the main LV panel select the option to change the program name from DWKLOGIC to the name of the file in which your function will reside (this can be identical to the name of the function) and change the programming language to C.

8. From the main LV panel select the option to bind the function.

9. From the main LV panel select the option to create the C-Language AIM file (II file) for the function.

10. From the main LV panel select the option to create a report on the new function.

11. Exit RM.

12. Run the EDMM-Productivity Facility program. Specify the System: CMS, MVS, etc. Specify the The FUNCTION type: UNLOAD, LOAD, DELETE, COPY, or CF.

a. Unload

A function that retrieves a group of connected entities and relationships from the repository and translates the entity, attribute, and relationship information via the Builder function into a CDF data stream.

This function takes any root key as input (i.e. dependent keys and/or user assigned keys).

b. Load

A function that interprets a CDF data stream containing entity, attribute, and relationship information, updating the repository as specified by the action field of each CDF unit.

c. Delete

A function that deletes a group of connected entity and relationship instances from the repository.

d. Copy

A function that copies a group of connected entity and relationship instances in the repository.

e. CF

A function that provides data transfer and remote function routing between the work station and the host platforms.

Enter the function name (Ex.EDXUD00):

Enter the name of the function (this is the target function name used above). Enter the program name (Ex. EDXUD00C):

Enter the name of the program (this is the name that you specified earlier, it may be identical to the function name).

Enter the Aggregation name (Ex. DBD Definition):

Enter a string that names the object that the function operates on. It does not have to be a defined aggregation name.

UNLOAD generation complete . . .

Source code is in RM120.EDMMSRC0(MYUNLOAD)

LEL is in RM120.EDMMLEL0(MYUNLOAD)

If the function is successfully created a message will indicate where the newly created source code and lel file reside.

13. After the new data handling function has created, compile the function using the C/370 compiler.

14. Link Edit the new function.

FUNCTION INVOCATION EXAMPLES

This section describes the work station steps necessary for invoking the host functions via EDMM. This description is achieved by use of examples and comments describing the behavior. Each example illustrates the use of regular parameters (input and output), a scenario on building the data for EDMM and a scenario on parsing the data returned from the function via EDMM. There are four examples: the first example demonstrates the invocation of a function without any CDF data; the second example has CDF data as input to the host function: the third has CDF data returned back from the host function: and the last example includes the use of CDF data as input and output to the host function.

Function with No CDF Data

Following is the work station activity necessary to invoke a function (DELETE) that has no special CDF data. Assume that the DELETE function interface is as follows:

    ______________________________________                                         Function Name: DELETE                                                          ______________________________________                                         (In) SYSKEY      Fixed        31                                               (In) AGG.sub.-- TYPE                                                                            Char         32                                               (In) COMMIT      Char          1                                               (Out) SC         Fixed        16                                               (Out) CC         Char          8                                               ______________________________________                                    

1. The Builder is invoked multiple times to build the data stream for EDMM. Note: Only input data needs to be put in the data stream. Output parameters do not need to be built into the data stream.

                                      TABLE 2                                      __________________________________________________________________________     Building CDF Data Stream                                                       __________________________________________________________________________                          Data-> Name                                                                    Data-> Value                                              Builder              Data-> Temp.sub.-- Key                                    Function                                                                             ID        Action                                                                              Data-> Rel.sub.-- Posn                                                                    Notes                                          __________________________________________________________________________     FIRST EDMM.sub.-- DATA.sub.--                                                                  NONE --         Tells the Builder                                    STREAM.sub.-- ID                                                                              --         to build a CDF                                                      --         data stream for                                                     --         EDMM                                           NEXT  FUN.sub.-- CALL.sub.-- ID                                                                NONE DELETE     Adds function                                                       --         name to the                                                         --         CDF data stream                                                     --                                                        NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE SYSKEY     Adds SYSKEY                                                         2022654    input parameter                                                     --         to the CDF data                                                     --         stream                                         NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE AGG.sub.-- TYPE                                                                           Adds                                                                DLI.sub.-- DBD.sub.-- DEF                                                                 AGG.sub.-- TYPE                                                     --         input parameter                                                     --         to the CDF data                                                                stream                                         NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE COMMIT     Adds COMMIT                                                         Y          input parameter                                                     --         to the CDF data                                                     --         stream                                         WRITE.sub.--                                                                         (ignored) (ignored)                                                                           --         Builder returns                                MEM                  --         address of the                                                      --         EDMM Data                                                           --         Stream (The                                                                    WRITE.sub.-- FILE                                                              builder function                                                               could also have                                                                been used . . . in                                                             this case the data                                                             is returned in a                                                               file specified by                                                              the caller.)                                   __________________________________________________________________________      Note:                                                                          This table emphasizes the input parameters that pertain to this scenario.

2. After creating the EDMM Data Stream, the EDMM communication function can be invoked:

    rc=egppt00(cdf.sub.-- filename, &cdf.sub.-- memaddr, cc);.

The edf₋₋ filename would be a null string in this case, since the EDMM Data Stream is in the memory block pointed to by cdf₋₋ memaddr.

3. Upon completion of the DELETE function, egppt00 returns with an output EDMM Data Stream. This information can be read via multiple invocations of the parser.

Note: The caller must release the memory for the CDF data stream returned by EDMM. A function will be provided to perform this action.

Following are the steps necessary to read the data:

                                      TABLE 3                                      __________________________________________________________________________     Parsing Output CDF Data Stream                                                 __________________________________________________________________________                           Data-> Name                                                                    Data-> Value                                             Parser                Data-> Temp.sub.-- Key                                   Function                                                                             ID         Action                                                                              Data-> Rel.sub.-- Posn                                                                    Notes                                         __________________________________________________________________________     FIRST EDMM.sub.-- DATA.sub.--                                                                   NONE --                                                             STREAM.sub.-- ID                                                                               --                                                                             --                                                                             --                                                       NEXT  FUN.sub.-- CALL.sub.-- ID                                                                 NONE DELETE                                                                         --                                                                             --                                                                             --                                                       NFXT  FUN.sub.-- PARM.sub.-- ID                                                                 NONE SC                                                                             0                                                                              --                                                                             --                                                       NEXT  FUN.sub.-- PARM.sub.-- ID                                                                 NONE CC                                                                             CC.sub.-- OK                                                                   --                                                                             --                                                       __________________________________________________________________________      Note:                                                                          This table only shows the output parameters that pertain to this scenario                                                                               

Function with CDF Data as an Input Parameter

Following is the work station activity necessary to invoke a host function that requires CDF data as input. Assume that the function interface is as follows:

    ______________________________________                                         Function Name: MAINTAIN                                                        ______________________________________                                         (In) SYSKEY        Fixed   31                                                  (In) AGG.sub.-- TYPE                                                                              Char    32                                                  (In) CDF.sub.-- MEM                                                                               Fixed   32                                                  (In) CDF.sub.-- FILE                                                                              Char    46                                                  (In) COMMIT        Char     1                                                  (Out) SC           Fixed   16                                                  (Out) CC           Char     8                                                  ______________________________________                                    

1. Following are the steps necessary to build the data stream for EDMM. Note: Only input data needs to be put in the data stream.

                                      TABLE 4                                      __________________________________________________________________________     Building CDF Data Stream for Maintain                                                                 Data->Name                                                                     Data->Value                                             Builder                Data->Temp.sub.-- Key                                   Function                                                                             ID         Action                                                                               Data->Rel.sub.-- Posn                                                                     Notes                                        __________________________________________________________________________     FIRST EDMM.sub.-- DATA.sub.--                                                                   NONE  --         Tells the Builder                                  STREAM.sub.-- ID --         to build a CDF                                                      --         data stream for                                                     --         EDMM                                         NEXT  FUN.sub.-- CALL.sub.-- ID                                                                 NONE  MAINTAIN   Adds function                                                       --         name to the                                                         --         CDF data stream                                                     --                                                      NEXT  FUN.sub.-- PARM.sub.-- ID                                                                 NONE  SYSKEY     Adds SYSKEY                                                         1123009    input parameter                                                     --         to the CDF data                                                     --         stream                                       NEXT  FUN.sub.-- PARM.sub.-- ID                                                                 NONE  AGG.sub.-- TYPE                                                                           Adds                                                                DLI.sub.-- DBD.sub.-- DEF                                                                 AGG.sub.-- TYPE                                                     --         input parameter                                                     --         to the CDF data                                                                stream                                       NEXT  FUN.sub.-- PARM.sub.-- ID                                                                 NONE  COMMIT     Adds COMMIT                                                         Y          input parameter                                                     --         to the CDF data                                                     --         stream                                       NEXT  ER.sub.-- DATA.sub.-- GROUP                                                               NONE  --         If the                                                              --         ER.sub.-- DATA.sub.--                                               --         GROUP has                                                           --         already been                                                                   created, a build                                                               function of                                                                    ADD.sub.-- STREAM                                                              should be used to                                                              add the complete                                                               ER.sub.-- DATA.sub.--                                                          GROUP data                                                                     stream into the                                                                current data stream.                         NEXT  TEMPL.sub.-- ID                                                                           UPDATE                                                                               DLI.sub.-- DBD                                                                            Adds template id                                                    --         to the CDF data                                                     --         stream                                                              --                                                      NEXT  TMPL.sub.-- KEY.sub.-- ID                                                                 NONE  --         Adds template                                                       1123009    key to the CDF                                                      --         data stream                                                         --                                                      NEXT  FIELD.sub.-- ID                                                                           UPDATE                                                                               ACCESS     Updates template                                                    HDAM       field to the CDF                                                    --         data stream                                                         --         (These NEXT                                                                    calls continue for                                                             each Template                                                                  unit and Relationship)                       WRITE.sub.--                                                                         (ignored)  (ignored)                                                                            --         Builder returns                              MEM                    --         address of the                                                      --         EDMM Data                                                           --         Stream. (The                                                                   WRITE.sub.-- FILE                                                              builder function                                                               should also have                                                               been used. In                                                                  this case the data                                                             is returned in a                                                               file specified by                                                              the caller.)                                 __________________________________________________________________________      Note: This table emphasizes the input parameters that pertain to this          scenario.                                                                

It should be noted here that the CDF₋₋ FILE and CDF₋₋ MEM in the Maintain Parameter template actually refer to the host filename and the host memory location of the CDF data. Since it would be unnatural for the work station application to specify these values, the EDMM communication Facility recognizes the CDF data group associated with the function call and sets the host function parameters with the appropriate data.

2. After creating the EDMM Data Stream, the EDMM communication Facility can be invoked:

    rc=egppt00(cdf.sub.-- filename, &cdf.sub.-- memaddr,cc):

The cdf₋₋ filename should be a null string in this case, since the EDMM Data Stream is in the memory block pointed to by cdf₋₋ memaddr.

3. Upon return completion of the MAINTAIn Facility, egppt00 returns with an output EDMM Data Stream. This information can be read via the parser.

Note: The caller must release the memory for the CDF data stream returned by EDMM. A function will be provided to perform this action.

Following are the step necessary to read the data:

                                      TABLE 5                                      __________________________________________________________________________     Parsing Output CDF Data Stream                                                                       Data->Name                                                                     Data->Value                                              Parser                Data->Temp.sub.-- Key                                    Function                                                                             ID         Action                                                                              Data->Rel.sub.-- Posn                                                                      Notes                                        __________________________________________________________________________     FIRST EDMM.sub.-- DATA.sub.--                                                                   NONE --                                                             STREAM.sub.-- ID                                                                               --                                                                             --                                                                             --                                                       NEXT  FUN.sub.-- CALL.sub.-- ID                                                                 NONE MAINTAIN                                                                       --                                                                             --                                                                             --                                                       NEXT  FUN.sub.-- PARM.sub.-- ID                                                                 NONE SC                                                                             0                                                                              --                                                                             --                                                       NEXT  FUN.sub.-- PARM.sub.-- ID                                                                 NONE CC                                                                             CC.sub.-- OK                                                                   --                                                                             --                                                       __________________________________________________________________________      Note: This table only shows the output parameters that pertain to this         scenario.                                                                

Function with CDF Data as an Output Parameter

Following is the work station activity necessary to invoke a host function that has CDF data as Output. Assume that the function interface is as follows:

    ______________________________________                                         Function Name: UNLOAD                                                          ______________________________________                                         (In) SYSKEY        Fixed   31                                                  (In) AGG.sub.-- TYPE                                                                              Char    32                                                  (In) LOCKTYPE      Char     8                                                  (In) HOLDLOCK      Char     1                                                  (Out) CDF.sub.-- MEM                                                                              Fixed   32                                                  (Out) CDF.sub.-- FILE                                                                             Char    46                                                  (Out) SC           Fixed   16                                                  (Out) CC           Char     8                                                  ______________________________________                                    

1. Following are the steps necessary to build the data stream for EDMM.

                                      TABLE 6                                      __________________________________________________________________________     Building CDF Data Stream for Maintain                                                               Data->Name                                                                     Data->Value                                               Builder              Data->Temp.sub.-- Key                                     Function                                                                             ID        Action                                                                              Data->Rel.sub.-- Posn                                                                     Notes                                          __________________________________________________________________________     FIRST EDMM.sub.-- DATA.sub.--                                                                  NONE --         Tells the Builder                                    STREAM.sub.-- ID                                                                              --         to build a CDF                                                      --         data stream for                                                     --         EDMM                                           NEXT  FUN.sub.-- CALL.sub.-- ID                                                                NONE UNLOAD     Adds function                                                       --         name to the                                                         --         CDF data stream                                                     --                                                        NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE SYSKEY     Adds SYSKEY                                                         6674001    input parameter                                                     --         to the CDF data                                                     --         stream                                         NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE AGG.sub.-- TYPE                                                                           Adds                                                                DLI.sub.-- DBD.sub.-- DEF                                                                 AGG.sub.-- TYPE                                                     --         input parameter                                                     --         to the CDF data stream                         NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE LOCKTYPE   Adds                                                                NOUPDATE   LOCKTYPE                                                            --         input parameter                                                     --         to the CDF data stream                         NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE HOLDLOCK   Adds                                                                N          HOLDLOCK                                                            --         input parameter                                                     --         to the CDF data stream                         WRITE.sub.--                                                                         (ignored) (ignored)                                                                           --         Builder returns                                FILE                 --         the data in a file                                                  --         whose name is                                                       --         specified by the                                                               caller. As in the                                                              example before,                                                                the data could                                                                 have been placed                                                               in memory if the                                                               WRITE.sub.-- MEM                                                               function was employed.                         __________________________________________________________________________      Note: This table emphasizes the input parameters that pertain to this          scenario.                                                                

Once again, it should be noted here that the CDF₋₋ FILE and CDF₋₋ MEM parameters in the UNLOAD parameter list refer to the host filename and the host memory of the CDF data. Since it would be unnatural for the work station application to specify these values, the EDMM communication Facility recognizes the CDF data group associated with the function call and sets the host function parameters with the appropriate data.

2. After creating the EDMM Data stream, the EDMM communication Facility can be invoked:

    rc=egppt00(cdf.sub.-- filename, &cdf.sub.-- memaddr, cc):

The cdf₋₋ filename contains the name of the file that the user specified to the Builder for the WRITE₋₋ FILE function. The cdf₋₋ memptr should be set to NULL.

3. Upon completion of the MAINTAIn Facility, egppt00 returns with an output EDMM Data Stream. This information can be read via the parser.

Note: The caller must release the memory for the CDF data stream returned by EDMM. A function will be provided to perform this action.

Following are the step necessary to read the data:

                                      TABLE 7                                      __________________________________________________________________________     Parsing Output CDF Data Stream                                                 __________________________________________________________________________                           Data-> Name                                                                    Data-> Value                                             Parser                Data-> Temp.sub.-- Key                                   Function                                                                            ID         Action                                                                               Data-> Rel.sub.-- Posn                                                                    Notes                                         __________________________________________________________________________     FIRST                                                                               EDMM.sub.-- DATA.sub.--                                                                   NONE  --                                                            STREAM.sub.-- ID --                                                                             --                                                                             --                                                                             --                                                       NEXT FUN.sub.-- CALL.sub.-- ID                                                                 NONE  UNLOAD                                                                         --                                                                             --                                                                             --                                                       NEXT FUN.sub.-- PARM.sub.-- ID                                                                 NONE  SC                                                                             0                                                                              --                                                                             --                                                       NEXT FUN.sub.-- PARM.sub.-- ID                                                                 CC    CC.sub.-- OK                                                                   --                                                                             --                                                                             --                                                       NEXT ER.sub.-- DATA.sub.-- GROUP                                                               NONE  --                                                                             --                                                                             --                                                                             --                                                       NEXT TEMPL.sub.-- ID                                                                           DLI.sub.-- DBD                                                                       --                                                                             --                                                                             --                                                                             --                                                       NEXT TMPL.sub.-- KEY.sub.-- ID                                                                 NONE  DLI.sub.-- DBD                                                                 6674001                                                                        --                                                                             --                                                       NEXT FIELD.sub.-- ID                                                                           NONE  NAME                                                                           DBDI                                                                           --                                                                             --                                                       NEXT The rest of the                                                           `. . .`                                                                             Templates and                                                                  Relationships for the                                                          Aggregation Instance.                                                     __________________________________________________________________________      Note:                                                                          This table only show the output parameters that pertain to this scenario.

Function with CDF Data as Input and Output Parameters

Following is the work station activity necessary to invoke a host function that has CDF data as Output. Assume that the function interface is as follows:

    ______________________________________                                         Function Name: SRCMEM                                                          ______________________________________                                         (In) SRCLIB      Char         44                                               (In/Out) CDF.sub.-- MEM                                                                         Fixed        32                                               (In/Out) CDF.sub.-- FILE                                                                        Char         46                                               (Out) SC         Fixed        16                                               (Out) CC         Char          8                                               ______________________________________                                    

1. Following are the steps necessary to build the data stream for EDMM.

                                      TABLE 8                                      __________________________________________________________________________     Building CDF Data Stream for SRCMEM Function                                   __________________________________________________________________________                           Data-> Name                                                                    Data-> Value                                             Builder               Data-> Temp.sub.-- Key                                   Function                                                                             ID        Action                                                                               Data->Rel.sub.-- Posn                                                                     Notes                                         __________________________________________________________________________     FIRST EDMM.sub.-- DATA.sub.--                                                                  NONE  --         Tells the Builder                                   STREAM.sub.-- ID                                                                               --         to build a CDF                                                      --         data stream for                                                     --         EDMM                                          NEXT  FUN.sub.-- CALL.sub.-- ID                                                                NONE  SRCMEM     Adds function                                                       --         name to the                                                         --         CDF data stream                                                     --                                                       NEXT  FUN.sub.-- PARM.sub.-- ID                                                                NONE  SRCLIB     Adds SRCLIB                                                         LIB1       input parameter                                                     --         to the CDF data                                                     --         stream                                        NEXT  FILE.sub.-- DATA.sub.--                                                                  NONE  --         Adds FILE                                           GROUP.sub.-- ID --         DATA GROUP                                                          --         to the CDF data                                                     --         stream                                        NEXT  LINE.sub.-- ID                                                                           NONE  --         Adds member                                                         MEMBER1    name as line unit                                                   --         to the CDF data                                                     --         stream                                        NEXT  LINE.sub.-- ID                                                                           NONE  --         Adds member                                                         MEMBER2    name as line unit                                                   --         to the CDF data                                                     --         stream                                        NEXT  LINE.sub.-- ID                                                                           NONE  --         Adds member                                                         MEMBERn    name as line unit                                                   --         to the CDF data                                                     --         stream                                        WRITE.sub.--                                                                         (ignored) (ignored)                                                                            --         Builder returns                               FILE                  --         the data in a file                                                  --         whose name is                                                       --         specified by the                                                               caller. The data                                                               would have been                                                                placed in                                                                      memory if the                                                                  WRITE.sub.-- MEM                                                               function was                                                                   employed.                                     __________________________________________________________________________      Note:                                                                          This table emphasizes the input parameters that pertain to this scenario.

Once again, it should be noted here that CDF₋₋ FILE and CDF₋₋ MEM parameters in the SRCMEM parameter list refer to the host filename and the host memory location of the CDF data. Since it would be unnatural for the Work station application to specify these values, the EDMM communication Facility recognizes the File data group associated with the function call and sets the host function parameters with the appropriate data.

2. After creating the EDMM Data Stream, the EDMM communication Facility can be invoked:

    rc=egppt00(cdf.sub.-- filename, &cdf.sub.-- memaddr, cc):

The cdf₋₋ filename must contain the name of the file that the user specified to the builder for the WRITE₋₋ FILE function. The cdf₋₋ memptr should be set to NULL.

3. Upon return completion of the SRCMEM function, egppt00 returns with an output EDMM Data Stream. This information can be read via the parser.

Note: The caller must release the memory for the CDF data stream returned by EDMM. A function will be provided to perform this action.

Following are the steps necessary to read the data:

                                      TABLE 9                                      __________________________________________________________________________     Parsing Output CDF Data Stream                                                 __________________________________________________________________________                            Data-> Name                                                                    Data-> Value                                            Parser                 Data-> Temp.sub.-- Key                                  Function                                                                            ID           Action                                                                              Data-> Rel.sub.-- Posn                                                                    Notes                                        __________________________________________________________________________     FIRST                                                                               EDMM.sub.-- DATA.sub.--                                                                     NONE  --                                                          STREAM.sub.-- ID   --                                                                             --                                                                             --                                                     NEXT FUN.sub.-- CALL.sub.-- ID                                                                   NONE  SRCMEM                                                                         --                                                                             --                                                                             --                                                     NEXT FUN.sub.-- PARM.sub.-- ID                                                                   NONE  SC                                                                             0                                                                              --                                                                             --                                                     NEXT FUN.sub.-- PARM.sub.-- ID                                                                   NONE  CC                                                                             CC.sub.-- OK                                                                   --                                                                             --                                                     NEXT FILE.sub.-- DATA.sub.-- GROUP                                                               NONE  --                                                                             --                                                                             --                                                                             --                                                     NEXT LINE.sub.-- ID                                                                              NONE  --                                                                             Lib2                                                                           --                                                                             --                                                     __________________________________________________________________________      Note:                                                                          This table only show the output parameters that pertain to this scenario.

Using the foregoing specifications the invention may be implemented using standard programming techniques. The resulting program(s) may be stored on disk, diskettes, memory cards, ROM or any other memory device. For execution, the program may be copied into the RAM of the computer. One skilled in the art of computer science will easily be able to combine the software created as described with appropriate general purpose or special purpose computer hardware to create a system. While the preferred embodiment of the present invention has been illustrated in detail, it should be apparent that modifications and adaptations to that embodiment may occur to one skilled in the art without departing from the scope of the present invention as set forth in the following claims. 

What is claimed is:
 1. In a computer system having stored units of data, a computer implemented method comprising the steps of:(1) reading units of data from storage, each unit of data representing one of entity/relationship data, a function call, and file data; and (2) encoding all of said units of data using a common data format (CDF) according to formal CDF grammar rules to create a data stream comprising said encoded units of data.
 2. The method of claim 1, wherein step (2) comprises the steps of:(a) selecting one of said units of data; (b) generating a prefix for said selected unit of data; and (c) appending said prefix and said selected unit of data to said data stream; and (d) performing steps (a)-(c) for each of said units of data; wherein step (b) comprises the steps of:(i) encoding a length of said prefix and said selected unit of data into a length field of said prefix; (ii) encoding an action associated with said selected unit of data into an action field of said prefix; and (iii) encoding an identifier of said selected unit of data into an identifier field of said prefix.
 3. The method of claim 1, wherein the computer system is linked to a remote computer, the method further comprising the step of transmitting the data stream to the remote computer.
 4. The method of claim 3, further comprising the step of:associating an action with each unit of data, said each unit of data being manipulated according to said action by said remote computer.
 5. The method of claim 3, further comprising the step of parsing the data stream in the remote computer according to said formal CDF grammar rules to extract the units of data from the data stream.
 6. The method of claim 5, further comprising the steps executed in the remote computer of:detecting a function call in one of said extracted units of data; and passing the function call to a function processor for processing.
 7. The method of claim 6, further comprising the steps executed in the remote computer of:collecting one or more units of output data generated by execution of the function call in the remote computer; encoding said one or more units of output data using said common data format (CDF) according to said formal CDF grammar rules to create a second data stream comprising said encoded units of output data; and transmitting said second data stream to the computer system.
 8. The method of claim 7, further comprising the step executed in the computer system of parsing said second data stream to recover said units of output data.
 9. A computer system having stored units of data, comprising:means for reading units of data from storage, each unit of data representing one of entity/relationship data, a function call, and file data; and encoding means for encoding all of said units of data using a common data format (CDF) according to formal CDF grammar rules to create a data stream comprising said encoded units of data.
 10. The system of claim 9, wherein the computer system has a local and a remote computer connected by a communication link, the computer system further comprising means for transmitting the data stream from the local computer to the remote computer.
 11. The computer system of claim 10, wherein said encoding means comprises:association means for associating an action with each unit of data, said each unit of data being manipulated according to said action by said remote computer.
 12. The system of claim 10, further comprising:means in the remote computer for parsing the data stream to extract the units of data from the data stream.
 13. The system of claim 12, the remote computer further comprising:means for detecting a function call in one of said extracted units of data; means for processing the function call in the remote computer; means for collecting one or more units of output data generated by the processing of the function call in the remote computer; means for encoding said one or more units of output data using said common data format (CDF) according to said formal CDF grammar rules to create a second data stream comprising said encoded units of output data; means for transmitting said second data stream to the local computer; and means for parsing said second data stream in the local computer to recover the units of output data.
 14. A computer system, comprising:(a) a host computer; and (b) a workstation computer coupled to said host computer, including(1) means for retrieving a first unit of data from a storage device connected to said workstation computer, said first unit of data comprising a function call to retrieve entity/relationship data from a storage device connected to said host computer, (2) means for creating a first encoded unit of data having a common data format (CDF) according to formal CDF grammar rules, said first unit of data being embedded in said first encoded unit of data, (3) transferring said first encoded unit of data from said workstation computer to said host computer; said host computer comprising(i) means for enabling said host computer to extract said first unit of data from said first encoded unit of data according to said formal CDF grammar rules, (ii) means for enabling said host computer to process said function call contained in said first unit of data such that said host computer retrieves a second unit of data comprising entity/relationship data from said storage device connected to said host computer, (iii) means for creating a second encoded unit of data having said common data format according to said formal CDF grammar rules, said second unit of data being embedded in said second encoded unit of data, and (iv) means for transferring said second encoded unit of data from said host computer to said workstation computer.
 15. A computer implemented method for enabling multiple computer systems to access entity/relationship data, function calls, and file data stored in any of said computer systems, comprising the steps of:(1) reading in one of said computer systems an unit of data from a storage device coupled to said one of said computer systems, said unit of data representing one of entity/relationship data, a function call, and file data; (2) creating in said one of said computer systems an encoded unit of data having a common data format (CDF) according to formal CDF grammar rules, said unit of data being embedded in said encoded unit of data; (3) transferring a data stream comprising said encoded unit of data from said one of said computer systems to another of said computer systems; (4) parsing said data stream, in said another of said computer systems, according to said formal CDF grammar rules to extract said unit of data from said data stream; and (5) processing said extracted unit of data in said another of said computer systems. 